// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE-BSD file. See the AUTHORS file for names of contributors.

// SPDX-License-Identifier: Apache-2.0
// Copyright 2020, Intel Corporation

#ifndef STORAGE_LEVELDB_UTIL_MUTEXLOCK_H_
#define STORAGE_LEVELDB_UTIL_MUTEXLOCK_H_

#include "port/port_posix.h"
#include "port/thread_annotations.h"

namespace leveldb
{

// Helper class that locks a mutex on construction and unlocks the mutex when
// the destructor of the MutexLock object is invoked.
//
// Typical usage:
//
//   void MyClass::MyMethod() {
//     MutexLock l(&mu_);       // mu_ is an instance variable
//     ... some complex code, possibly with multiple return paths ...
//   }

class SCOPED_LOCKABLE MutexLock {
public:
	explicit MutexLock(port::Mutex *mu) EXCLUSIVE_LOCK_FUNCTION(mu) : mu_(mu)
	{
		this->mu_->Lock();
	}
	~MutexLock() UNLOCK_FUNCTION()
	{
		this->mu_->Unlock();
	}

private:
	port::Mutex *const mu_;
	// No copying allowed
	MutexLock(const MutexLock &);
	void operator=(const MutexLock &);
};

} // namespace leveldb

#endif // STORAGE_LEVELDB_UTIL_MUTEXLOCK_H_
